Seismic Response Research Of Liquid Storage Tank Based On Response Spectrum Method

Vertical cylindrical storage tanks are widely used in many industries mainly in the chemical industry to store crude oil,oil products and petrochemical liquid products.With the development of Chinese social economy,the use of storage tanks has gradually increased and the volume has gradually increased.In petrochemical enterprises,most of the raw materials stored are flammable and explosive liquid materials,so the safety of storage tanks is very important.Once the storage tank is structurally damaged in an earthquake,it is likely to cause large-scale leakage,fire and explosion,etc.The use experience shows that the storage tanks built according to the existing design standards are safe under normal conditions.However,the actual strong earthquake observation found that the storage tanks suffered various damages,indicating that the existing oil tank storage tank research theories and methods still exist Insufficient,and it is necessary to conduct in-depth research on the seismic resistance of storage tanks.At present,the seismic calculation of the liquid storage tank is mainly based on the equivalent mechanical model represented by the Housner model and the numerical method of fluid-solid coupling.The numerical method of fluid-solid coupling is theoretically accurate,but difficult to achieve in practice.There are various forms of equivalent mechanical models,and the scope of application is not accurate enough,and the national standards only give the general liquid storage tank structure.Based on this,the thesis sorts out and summarizes the existing models and methods of researching storage tanks to quickly and accurately solve the seismic problem of storage tank structures.The main work is as follows:(1)The equivalent mechanics model is introduced and discussed in detail,the equivalent parameters of different models are compared and analyzed,and the applicability of the equivalent mechanics model under the conditions of four liquid level heights is explained.The seismic response of the equivalent mechanical model was solved by using the response spectrum method,and compared with the norm and the finite element model considering the fluid-solid coupling.The response spectrum method of the kinetic model has good accuracy and can be widely used in practical engineering.(2)Considering the liquid storage pulse and convection effects,based on the basic principle of the Houner model,a finite element model of the additional mass distributed on the tank wall is established.Using the mode decomposition response spectrum method,the seismic response of the storage tank can be solved with less computational effort.the mechanical parameters such as local stress-strain and displacement at the vulnerable parts such as the tank wall and tank bottom can be observed.The equivalent mechanical model is supplemented and developed,and the calculation results of the specification are compared and analyzed,which proves the effectiveness of this method.(3)The effect combination method of applying the response spectrum method to the structure of the liquid storage tank under the action of two-way horizontal earthquake is discussed.Compared with the time-history analysis method,it is shown that the SRSS(square root of summation of squares method)effect combination method is suitable for solving the maximum reaction value in the seismic analysis of the liquid storage tank system using the response spectrum method.(4)The shaking table model experiment of the liquid storage tank system is carried out,and the spectrum analysis and seismic response analysis are carried out for the experiment.The experimental results and the numerical analysis results are compared and analyzed,the seismic effect combination problem under bidirectional horizontal earthquake action is studied,and the correctness of the numerical calculation method and conclusion is verified.